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[107.220.129.194]) by smtp.gmail.com with ESMTPSA id 00721157ae682-85e5e181596sm78013697b3.10.2026.09.01.08.51.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Sep 2026 08:51:34 -0700 (PDT) From: Matt Turner To: linux-alpha@vger.kernel.org, richard.henderson@linaro.org Cc: linmag7@gmail.com, linux-kernel@vger.kernel.org Subject: [PATCH 16/24] alpha: select HAVE_GUP_FAST Date: Tue, 1 Sep 2026 11:50:29 -0400 Message-ID: <96d45353c7c29cc3aaa3234bd960f38d2ed8889f.1788277742.git.mattst88@gmail.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-alpha@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The lockless GUP fast path needs the architecture to distinguish PTEs with no struct page behind them and to keep page table pages alive while a walker holds no lock. Alpha now has ARCH_HAS_PTE_SPECIAL, and it has selected MMU_GATHER_RCU_TABLE_FREE for a long time, so both requirements are met. PTEs are a single 64-bit word on Alpha, so the lockless reads that the generic walker performs cannot tear, and no arch-specific gup_fast_permitted() or ptep_get_lockless() is needed. Assisted-by: Claude:claude-opus-5 Signed-off-by: Matt Turner --- arch/alpha/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git ./arch/alpha/Kconfig ./arch/alpha/Kconfig index 87fe81bc4709..352615956b1e 100644 --- ./arch/alpha/Kconfig +++ ./arch/alpha/Kconfig @@ -26,6 +26,7 @@ config ALPHA select HAVE_ARCH_COMPILER_H select HAVE_ASM_MODVERSIONS select HAVE_DEBUG_KMEMLEAK + select HAVE_GUP_FAST select HAVE_PAGE_SIZE_8KB select HAVE_PCSPKR_PLATFORM select HAVE_PERF_EVENTS -- 2.54.0